Attempt to fix some -Woverloaded-virtual warnings.

fpdfsdk/src/pdfwindow/PWL_SpecialButton.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
  
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "../../include/pdfwindow/PDFWindow.h"
 #include "../../include/pdfwindow/PWL_Wnd.h"
 #include "../../include/pdfwindow/PWL_Button.h"
 #include "../../include/pdfwindow/PWL_SpecialButton.h"
@@ skipping 37 matching lines @@
 void CPWL_CheckBox::SetCheck(FX_BOOL bCheck)
 {
         m_bChecked = bCheck;
 }
 
 FX_BOOL CPWL_CheckBox::IsChecked() const
 {
         return m_bChecked;
 }
 
-FX_BOOL CPWL_CheckBox::OnLButtonUp(const CPDF_Point & point)
+FX_BOOL CPWL_CheckBox::OnLButtonUp(const CPDF_Point & point, FX_DWORD nFlag)
 {
         if (IsReadOnly()) return FALSE;
 
         SetCheck(!IsChecked());
         return TRUE;
 }
 
-FX_BOOL CPWL_CheckBox::OnChar(FX_WORD nChar)
+FX_BOOL CPWL_CheckBox::OnChar(FX_WORD nChar, FX_DWORD nFlag)
 {
         SetCheck(!IsChecked());
         return TRUE;
 }
 
 /* --------------------------- CPWL_RadioButton ---------------------------- */
 
 CPWL_RadioButton::CPWL_RadioButton() : m_bChecked(FALSE)
 {
 }
 
 CPWL_RadioButton::~CPWL_RadioButton()
 {
 }
 
 CFX_ByteString CPWL_RadioButton::GetClassName() const
 {
         return "CPWL_RadioButton";
 }
 
-FX_BOOL CPWL_RadioButton::OnLButtonUp(const CPDF_Point & point)
+FX_BOOL CPWL_RadioButton::OnLButtonUp(const CPDF_Point & point, FX_DWORD nFlag)
 {
         if (IsReadOnly()) return FALSE;
 
         SetCheck(TRUE);
         return TRUE;
 }
 
 void CPWL_RadioButton::SetCheck(FX_BOOL bCheck)
 {
         m_bChecked = bCheck;
 }
 
 FX_BOOL CPWL_RadioButton::IsChecked() const
 {
         return m_bChecked;
 }
 
-FX_BOOL CPWL_RadioButton::OnChar(FX_WORD nChar)
+FX_BOOL CPWL_RadioButton::OnChar(FX_WORD nChar, FX_DWORD nFlag)
 {
         SetCheck(TRUE);
         return TRUE;
 }